INTRODUCTION
In 1999 the Nobel Prize in Physiology or Medicine was awarded to Gunter Blobel for the discovery that proteins have intrinsic signals that govern their transport and localisation in the cell. It was based on this research into how cells use these signals that the functions of glycoproteins were discovered.
Glycoproteins are molecules that have a sugars and protein bonded together. The sugar chains of glycoproteins play a role in determining their destination in the cell or body. The bonding of sugars to proteins to form glycoproteins significantly alters the properties of these proteins.
There are eight sugars that predominantly bond with proteins to form glycoproteins, these are: xylose, galactose, glucose, mannose, fucose, N-acetylgalactosamine, N-acetylglucosamine and N-acetylneuraminic acid.
WHAT ARE THE FUNCTIONS OF GLYCOPROTEINS?
Glycans contain biologic information and are the specific sequence of sugars in a glycoprotein that determine its recognition and interaction with other molecules in the cell, often resulting in a biologic effect or response. These impart their function to glycoproteins.
Glycoproteins have many functions in the human body. A few functions of interest is that they are used structurally in the body to form some types of collagen; or are involved in cell-cell interactions, such as in the proteins involved in sperm-egg interactions during fertilisation or how cells stick together to form tissues and communicate with each other. They also function in cell signalling.
Cell signaling is the related study of how healthy cells respond appropriately in health to various stimuli e.g., hormones, growth factors, drugs, cell-cell contact, etc. Glycoproteins on the surface of one cell bind to glycoprotein receptors on another cell, which allows the cells to communicate with one another. These communications then result in other cellular events, such as secretion of bioactive substances, killing of bacteria and cell debris, inhibition of adherence necessary for bacterial infection. Conversely, the responses may be inappropriate in certain diseases, such as cancer and cancer cell metastasis.
Lectins, for example, are proteins that selectively bind glycans. One lectin will recognize and bind mannose at the end of a glycan, whereas others will recognize and bind to glycans containing fucose, galactose, or other sugars. A class of lectins called selectins helps white blood cells to sites of inflammation.
WHAT IS GLYCONUTRITION?
Glyconutrition is the supplementation the 8 principal sugars that are needed by the body to from glycoproteins. They are considered essential nutrients, much the same as essential amino acids or essential fatty acids, which means you have to get them from your diet.
WHY IS GLYCONUTRITION CONSIDERED ESSENTIAL?
Metabolic pathways exist for synthesis of non-glucose sugars from glucose, and it has long been thought that glucose is the most important dietary sugar; it has recently been shown that glycoprotein formation actually prefer to utilize non-glucose essential sugars (e.g. mannose) provided in the diet as substrates. In fact, if only glucose is supplied, the liver severely malfunctions, due to a lack of the other essential sugars, indicating that the body simply cannot synthesize all the other essential sugars from glucose to the extent that they are needed.
WHERE ARE THE 8 SUGARS OBTAINED FROM IN THE DIET?
These 8 sugars will only appear in fruit and vegetables that are vine ripened; this essentially means the fruit or vegetable ripens on the plant. However this is a process that no longer happens in modern agriculture. Much of our fruit and vegetables are picked when green, and artificially ripened prior to being put on the shelves at the supermarket. This means sadly that we have to supplement with them to obtain the eight necessary sugars essential for health.
HOW MAY CORRECT GLYCOPROTEIN FORMATION CONTRIBUTE TO DISEASE MANAGEMENT?
As can be seen from the preceding paragraphs, glycoproteins are vital in the health and maintenance of the human body; so much so, that extensive research has been conducted on them in relation to certain diseases.
Implications for cancer. Research has shown that there are changes to the sugars in glycoproteins of cancer cells. These changes relate to adhesion properties of the cancer cell and their ability to adhere to other cells in the body or to metastasize. These altered glycoproteins may also relate to the ability of the tumour to avoid the responses of the immune system. Altered glycoproteins have been found in intestinal, pancreatic, liver, ovarian, prostate, and lung cancers.
Glycoproteins that have mannose in their structure has been shown to activate macrophages (an immune system cell), one of the most important cells involved in fighting cancer. Also, the release of substances from the macrophage is stimulated, which activates natural killer cells (another immune system cell involved in the elimination of cancer cells).
Implications for chronic fatigue syndrome and fibromyalgia. The principle symptoms of these conditions include muscle and joint pain, chronic fatigue, non-restorative sleep, chronic tension, migraine headaches, and bowel and bladder irritability. The immune, endocrine (e.g. hormones), nervous (e.g. neurotransmitters, sleep pathways, psychological stress), and muscular (e.g. tender points) systems of the body are all intimately involved in these syndromes. Glycoproteins all play important roles in maintaining the health and normal functioning of these systems. Therefore supplementation with the 8 simple sugars may positively impact on these syndromes.
Implications for inflammation. Inflammation in itself is not a disease, but rather occurs as result of tissue injury, such as in bacterial infection. Inflammation is usually beneficial to the individual. However, this process can get out of hand, as many diseases that affect us are inflammatory in origin. As noted earlier, glycoproteins help guide immune cells to sites of inflammation, as well as they are involved in the process of allowing the immune cells to traverse the wall of blood vessels and enter the tissues at the site of inflammation.
Implications for peptic ulcers induced by Helicobacter pylori bacteria. Helicobacter pylori attach to 2 specific glycans on the cell surfaces of stomach and duodenum. Once attached, the bacteria release various enzymes that along with the acidic content of the stomach, results in ulceration. Glycans are the first molecules encountered by bacteria as a means to attach to cells. The 8 sugars compete with bacteria for attachment to the glycans, and is one way of blocking bacterial adherence.
Implications for stress. Research has shown that the formation of glycoproteins is significantly altered in various types of stress, such as in infection, inflammation and trauma.
Stress exists in many forms, whether it is psychological (as in nervous system dysfunction), environmental (as in extreme heat or chemical toxins) or physicochemical (such as in exercise). Glycoproteins prevent and repair damage to cells as a result of these stresses.
Implications for Rheumatoid Arthritis. Rheumatoid arthritis (RA) is an inflammatory condition, and glyconutritions are known to positively affect inflammation.
RA is an autoimmune condition, meaning that antibodies are produced against the body’s own tissues; this implies that there is a miscommunication between the immune system and the joint tissue. The abnormal antibody produced is IgG, which has less than normal amounts of galactose in its structure, and during remission this reduction of galactose is reversed.
It has also been found that fucose is markedly reduced in RA patients. The greater the deficiency of fucose in RA patients, the more severe the symptoms will be.
Supplementation of the necessary sugars, i.e. galactose and fucose, needed by the body to combat this illness.
On the topic of auto-immune conditions I would like to share a case of mine successfully treated with the ise of these 8 essential sugars. Mrs T. presented to me with discoid lupus, which is a milder case of lupus which predominantly affects the skin, causing hard ‘scar-like’ lesions. She had these lesions spread throughout the body. I prescribed the sugars in a powder, 5g/day. After using them for a period of 3 months, all of her skin lesions were completely healed, as well as her anti nuclear factor had dropped right down to normal blood levels.
In my personal experience with these sugars I have found that they are the best in treating auto-immune conditions such as lupus, rheumatoid arthritis, multiple sclerosis etc. If you have any questions regarding the use of the 8 sugars for your health condition/s, feel free to contact me.
CONCLUSION
As can be seen from the above article, proper glycoprotein formation plays an important role on the maintenance of health and combating of disease. Sadly six of the eight sugars no longer appear in our food supply, and it has become necessary to supplement with these sugars in order to maintain optimum health.